Field of the Invention
Embodiments of the present invention relate generally to associating two or more devices.
Description of the Related Art
Typically, electronic devices are paired using the Bluetooth™ technology. The term “pairing” means that two devices exchange some data to agree to work together to provide a predefined function. For example, a Bluetooth™ enabled mobile phone may be paired with a Bluetooth™ headset and upon a successful pairing, the headset provides speakers and microphone to the mobile phone.
There are many issues with the above stated method of pairing or associating two or more devices. First, a special hardware is needed at both ends to effect such pairing. Second, such pairing can only be used for prewired specific functions based on configured profiles. Also, the Bluetooth™ signals have wider range, hence, without a proper security, unintended pairing may occur. Another issue with the Bluetooth pairing is that the paired devices must stay within a physical proximity to each other after the pairing. Moreover, having extra hardware in devices can put more stress on device batteries.
Using digital codes in radio transmissions have been used in the past. For example, the National Weather Service, in the past, has used digital codes at the beginning and end of every message concerning life- or property-threatening weather conditions targeting a specific area. The inclusion of these digital codes produces a distinct sound which is easily recognized by most people as an emergency alert sounds.
Motorola two way radios also use transmission of data between two devices using audio frequency shift keying (AFSK). These radios have an option allowing the radio to filter out data bursts from the receive audio. Instead of hearing the AFSK data, the user hears a short chirp from the radio speaker each time a data burst occurs.
Hosei Matsuoka, Yusuke Nakashima, Takeshi Yoshimura, and Tashiro Kawahara. 2008. Acoustic OFDM: embedding high bit-rate data in audio. In Proceedings of the 14th international conference on Advances in multimedia modeling (MMM'08), Shin'ichi Satoh, Frank Nack, and Minoru Etoh (Eds.). Springer-Verlag, Berlin, Heidelberg, 498-507 (“Acoustic OFDM”) discloses a method of aerial acoustic communication in which data is modulated using OFDM (Orthogonal Frequency Division Multiplexing) and embedded in regular audio material without significantly degrading the quality of the original sound. It can provide data transmission of several hundred bps, which is much higher than is possible with other audio data hiding techniques. The proposed method replaces the high frequency band of the audio signal with OFDM carriers, each of which is power-controlled according to the spectrum envelope of the original audio signal. The implemented system enables the transmission of short text messages from loudspeakers to mobile handheld devices at a distance of around 3 m.
The above usages of the voice signals for communication includes sending the encoded signals over the audible part of a radio transmission and detecting these encoded signals at a receiver.